Decorated sheet for insert molding

ABSTRACT

Provided is a decorated sheet for insert molding in which at least a base sheet, a print layer and a surface resin layer are laminated, wherein the above base sheet comprises an ABS resin having a butadiene content of 10 to 33% by weight based on the total component, and the surface resin layer has a thickness of 50 to 150 μm. Capable of being provided is a novel decorated sheet which does not generate harmful gases such as a chlorine gas and the like in burning and therefore does not bring about problems such as environmental pollution and the like and which is excellent in a so-called vacuum molding property and can suitably be used for various interior decorations of automobiles and the like.

BACKGROUND OF THE INVENTION

The present invention relates to a decorated sheet for insert molding,more specifically to a decorated sheet for insert molding capable ofbeing suitably used in the fields such as interior decorations ofbuildings and automobiles in which a high design property is requiredand which are used for insert molding.

RELATED ART

Decorated sheets in which a base sheet, various print layers and asurface resin layer are laminated in order have so far been used fordecorations of wall papers, furniture, building materials, interiorparts of automobiles and the like.

In the fields of the above decorated sheets, vinyl chloride sheets,vinyl chloride-vinyl acetate copolymer sheets and the like have beenused as a base sheet. These sheets have the advantages that they areexcellent in a processing aptitude, a printing aptitude, an embossingaptitude and the like and can readily be controlled in a hardness byadding a plasticizer and that they are inexpensive, and therefore theyhave so far widely been used.

However, when vinyl chloride sheets and vinyl chloride-vinyl acetatecopolymer sheets are used as a base sheet constituting a decoratedsheet, a vinyl chloride monomer and hazardous gases such as chlorine gasand the like are likely to be generated in burning, and it is concernedabout that an incinerator used in burning is damaged and that theenvironment is contaminated, so that problems are involved therein.

In order to solve the above problems, a material of a base sheet ischanged to a material of a non-vinyl chloride base at present (forexample, patent documents 1 and 2).

A decorated sheet in which a polyolefin base resin is used for a basesheet is disclosed in the patent document 1, and a decorated sheet inwhich an acryl resin is used for a base sheet is disclosed in the patentdocument 2.

Patent document 1: Japanese Patent Application Laid-Open No. 16832/1994Patent document 2: Japanese Patent No. 2916130

DISCLOSURE OF THE INVENTION

However, the performances of the decorated sheets disclosed in the abovepatent documents are not necessarily satisfactory in some cases.

For example, when producing various parts for interior decoration ofautomobiles and the like, metallic and woodgrain decorated sheets areused in many cases at present, and these various parts are produced inalmost all cases by a so-called insert molding method in which adecorated sheet is set in advance in a die and in which a molten resinis then injected into the die to thereby mold a part integrally with thedecorated sheet. When used for the above application, problems have beencaused in many cases on an adhesive property with an adherend, a foldingprocessability and the like in the decorated sheets prepared by usingthe base sheets disclosed in the patent documents described above.Further, in the above insert molding method, a resin which is molten at220 to 240° C. in a die is pressed from a base sheet side of a decoratedsheet, and in such case, heat transferred from the resin is filled up inthe decorated sheet to allow an ink in a print layer to flow out, sothat the design property is damaged in a certain case.

The present invention has been made in light of the above circumstances,and an object thereof is to provide a novel decorated sheet which doesnot generate harmful gases such as a chlorine gas in burning andtherefore does not bring about problems such as environmental pollutionand which is excellent in a so-called insert molding property andtherefore can suitably be used for various interior decorations ofautomobiles and the like.

The present invention for achieving the object described above ischaracterized by a decorated sheet for insert molding in which at leasta base sheet, a print layer and a surface resin layer are laminated,wherein the above base sheet comprises an ABS resin having a butadienecontent of 10 to 33% by weight based on the total component, and thesurface resin layer has a thickness of 50 to 150 μm.

In the invention described above, the base sheet may have a Vicatsoftening temperature of 85 to 100° C. and a bend elastic modulus of1100 to 2000 MPa.

Further, in the invention described above, at least a thermoplasticresin may be contained in the print layer described above.

According to the invention described above, in the decorated sheet inwhich at least the base sheet, the print layer and the surface resinlayer are laminated, the base sheet described above is composed of theABS resin having a butadiene content of 10 to 33% by weight based on thetotal component, and therefore the decorated sheet can be provided withvarious characteristics with which the ABS resin is endowed, to bespecific, a rigidity, a hardness, a processability, an impactresistance, a bend fatigue property and the like.

Further, according to the invention described above, the ABS resin isnot simply used, and a content of butadiene constituting the ABS resinis limited to a prescribed value. In this respect, when using adecorated sheet in an insert molding method, the above decorated sheetis, as described above, brought into contact with a molten resin of 200°C. or higher, and according to the decorated sheet of the presentapplication, a distinct rubber odor originating in a butadiene componentcontained in the ABS resin for the base sheet is not produced to make itpossible to enhance the moldability. Accordingly, the decorated sheet ofthe present application can suitably be used for decoration of interiorpanels and the like of cars.

Further, in the decorated sheet of the present application, a thicknessof the surface resin layer is restricted to 50 to 150 μm, and thereforeeven when brought into contact with a molten resin of high temperature,heat transferred from the resin can be released, as described above, tothe die without allowing it to stay in the decorated sheet, so that anink constituting the print layer can be prevented from flowing out dueto heat to reduce the design property.

Further, a Vicat softening temperature of the base sheet comprising theABS resin is set to 85 to 100° C., and a bend elastic modulus thereof isset to 1100 to 2000 MPa, whereby the moldability in carrying out insertmolding can be improved more.

In the decorated sheet of the present application, the print layerdescribed above can contain at least a thermoplastic resin. Thedecorated sheet of the present application can prevent, as describedabove, the ink contained in the print layer from flowing out due toheat, and therefore thermoplastic resins which are easily affected byheat can be used as a binder component and the like to make it possibleto enhance a freedom degree in selecting the ink. Further, adding thethermoplastic resin to the print layer makes it possible to enhance aflexibility of the above print layer, which results in making itpossible to enhance a following property of the decorated sheet to thedie in insert molding and obtain an insert molded article having ahigher design.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an outline cross-sectional drawing for explaining theconstitution of the decorated sheet of the present invention.

EXPLANATIONS OF THE CODES

-   10 Decorated sheet-   11 Base sheet-   12 Print layer-   13 Surface resin layer

BEST MODE FOR CARRYING OUT THE INVENTION

The decorated sheet of the present invention shall specifically beexplained below with reference to the drawing.

FIG. 1 is an outline cross-sectional drawing for explaining theconstitution of the decorated sheet of the present invention.

As shown in FIG. 1, a decorated sheet 10 in the present invention isconstituted by laminating a base sheet 11, a print layer 12 and asurface resin layer 13.

(1) Base Sheet

The decorated sheet 10 of the present invention is characterized by thatthe base sheet 11 comprises an ABS resin having a butadiene content of10 to 33% by weight based on the total component. Using the above ABSresin as the base sheet not only makes it possible to improve thedecorated sheet and various characteristics, particularly an insertmoldability but also prevents a rubber odor from being generated evenwhen used for insert molding. Accordingly, it can suitably be used inproducing parts for interior decoration of cars and the like.

In this connection, the ABS resin constituting the decorated sheet 10 isa copolymer of acrylonitrile, butadiene and styrene.

In the present invention, the butadiene content is limited to the rangedescribed above because of the reasons that a butadiene content of lessthan 10% by weight raises a Vicat softening temperature of the decoratedsheet to elevate a bend elastic modulus thereof and that as a resultthereof, air discharge implemented in order to carry out insert moldingis deteriorated in vacuum molding to make a so-called freeze line liableto be brought about. Further, the high bend elastic modulus (rigidity)is likely to cause the problem that inferior laminate due to air fillingand slack is liable to be brought about when carrying out dry laminate.On the other hand, if the butadiene content exceeds 33% by weight, arubber odor is likely to be produced when the decorated sheet is usedfor an insert molding method, and the problem that the linear expansioncoefficient grows larger to make distortion liable to be caused byshrinkage in molding is likely to be brought about. The butadienecontent has to be 10 to 33% by weight, more preferably 24 to 33% byweight and particularly preferably 27 to 30% by weight based on thetotal component.

In the present invention, the contents of the other components(acrylonitrile and styrene) shall not specifically be restricted as longas the butadiene content is 10 to 33% by weight based on the totalcomponent, and they can suitably be set according to the expectedcharacteristics. For example, a content of acrylonitrile is preferably19 to 48% by weight based on the total component, and on the other hand,a content of styrene is preferably 38 to 48% by weight based on thetotal component. It is a matter of course that the contents of thesecomponents have to be set so that they account for 100% by weight intotal.

The base sheet 11 in the decorated sheet 10 of the present invention haspreferably a Vicat softening temperature of 85 to 100° C. and a bendelastic modulus of 1100 to 2000 MPa. Setting the Vicat softeningtemperature and the bend elastic modulus to the above values makes itpossible to enhance the characteristics of the decorated sheet,particularly an insert molding property.

In this connection, the Vicat softening temperature is defined by atemperature of a medium (a heating bath or a heating phase) observedwhen an acicular indentator set vertically to a test piece penetratesinto the test piece by 1 mm, wherein the test piece is disposed in theheating bath or the heating phase, and the medium is heated at aconstant rate while applying a prescribed load to the test piece throughthe acicular indentator. In the present invention, the Vicat softeningtemperature is a value determined by a measuring method specified in JISK 7206.

If a value of the Vicat softening temperature is lower than 85° C., aso-called orange peel is produced in a continuous heat resistant test,and the heat resistant creep is reduced in a certain case. On the otherhand, if a value of the Vicat softening temperature is higher than 100°C., air filling is brought about in laminating, and foaming is caused invacuum molding in a certain case.

In the present invention, the bend elastic modulus is a value determinedby a measuring method prescribed in ISO 178.

If a value of the bend elastic modulus is smaller than 1100 MPa, therigidity is reduced. On the other hand, if the value of the bend elasticmodulus is larger than 2000 MPa, it is difficult in a certain case toremove slack in continuous dry laminate. The value of the bend elasticmodulus falls more preferably in a range of 1100 to 1300 MPa in terms ofthe rigidity and removal of slack.

A thickness of the base sheet 11 in the decorated sheet 10 of thepresent invention shall not specifically be restricted in the presentapplication, and it can suitably be selected according to the uses. Itmay be, for example, about 300 to 700 μm, and it is preferably 400 to600 μm considering the insert moldability.

Further, if the whole part of the decorated sheet 10 is increased in athickness, not only it is increased as well in a cost, but also thedecorated sheet is pulled by flow of the injected molten resin in insertmolding, so that wrinkles are produced at the both ends in a certaincase. Accordingly, a thickness of the whole part of the decorated sheet10 is preferably about 2.5 to 3.0 mm.

(2) Print Layer

Next, the print layer 12 in the decorated sheet 10 of the presentinvention shall be explained.

The print layer 12 is a layer formed from an ink by a publicly knownprinting method such as, for example, gravure printing, offset printing,silk screen printing, transfer printing from a transfer sheet,sublimation transfer printing, ink jet printing and the like. Inaddition thereto, in the case of a whole solid pattern, it may be formedfrom a coating material by a publicly known coating method such asgravure coating, roll coating and the like.

The pattern of the print layer 12 shall not specifically be restrictedand can suitably be selected according to the uses, and it includes, forexample, woodgrain patterns, marble grain patterns, texture grainpatterns, leather tying patterns, geometric figures, characters,symbols, whole solid patterns and the like. The print layer 12 is usedas well in combination of a pattern layer expressing patterns such aswoodgrain patterns and the like with a whole solid layer. The wholesolid layer is used usually in the form of a masking layer, a colorlayer, a color masking layer and the like.

The print layer 12 is formed usually on the base sheet 11 by printing,and therefore it is formed, as shown in FIG. 1, on the surface side ofthe base sheet 11, but it shall not be restricted to the aboveembodiment and can be formed on the back surface and the both front andback surfaces of the base sheet 11 or the back surface, the frontsurface and the both front and back surfaces of a surface resin layerdescribed later.

Various kinds of polyester resins, urethane resins, acryl resins, vinylacetate resins, vinyl chloride-vinyl acetate copolymers, cellulose basereins and chlorinated polyolefin resins such as chlorinatedpolyethylene, chlorinated polypropylene and the like can be used aloneor in a mixture of two or more kinds thereof as a binder for an ink or acoating material used for forming the print layer 12 constituting thedecorated sheet 10 of the present invention, and it shall notspecifically be restricted. In the present invention, however,thermoplastic resins out of them are preferably added, and among them,polyester-urethane resins are preferably used. This is because of thereasons that a balance between a thermoplastic action of the polyestercomponent and a thermosetting action of the urethane component is mostsuited and that the heat resistance and the moldability are good aswell.

In this regard, chlorinated polyolefin resins are resins containingchlorine and therefore are not preferably used.

A colorant used for the ink or the coating material described aboveincludes inorganic pigments such as titan white, zinc oxide, iron oxidered, vermilion, ultramarine blue, cobalt blue, titan yellow, chromeyellow, carbon black and the like, organic pigments (including dyes)such as isoindolinone yellow, Hansa yellow A, quinacridone red,permanent red 4R, phthalocyanine blue, indathrene blue RS, aniline blackand the like, metal pigments comprising metal powders of aluminum, brassand the like, pearl pigments comprising flake powders of titaniumdioxide-covered mica, basic lead carbonate and the like, fluorescentpigments and the like. They can be used alone or in a mixture of two ormore kinds thereof.

The above print layer 12 is one of representative layers which areformed as layers for providing the decorated sheet with decorativepatterns, and a metal thin film layer and the like may be formed thereonin order to enhance more a decorativeness of the above print layer 12.The metal thin film layer can be formed by a method such as vacuum vapordeposition, sputtering and the like using metal such as aluminum,chromium, gold, silver, copper and the like. The above metal thin filmlayer may be provided on the whole surface or partially in a patternform.

(3) Surface Resin Layer

Next, the surface resin layer 13 in the decorated sheet 10 of thepresent invention shall be explained.

The surface resin layer 13 in the present invention is a layer which ispositioned on the surface of the decorated sheet 10 and which is formedfor the purposes of protecting the print layer 12 described above andproviding the decorated sheet 10 with various effects according to uses.

In the present application, the materials thereof shall not specificallybe restricted, and various resins can be used. To be specific, theyinclude, for example, resins such as acryls, polyesters, polypropylene,ethylene-vinyl alcohol copolymers, polycarbonate, cellulose triacetateand the like. Among them, acryl resins are preferably used consideringthe insert moldability, the weatherability and the surface hardness.

In this respect, the acryl resins include acryl resins comprisinghomopolymers or copolymers containing (meth)acrylic esters such aspolymethyl (meth)acrylate, polyethyl (meth)acrylate, polypropyl(meth)acrylate, polybutyl (meth)acrylate, methyl (meth)acrylate•butyl(meth)acrylate copolymers, ethyl (meth)acrylate•butyl (meth)acrylatecopolymers, ethylene•methyl (meth)acrylate copolymers, styrene•methyl(meth)acrylate copolymers and the like (provided that methyl(meth)acrylate means methyl acrylate or methyl methacrylate, andhereinafter (meth) shall have the same meaning). In the case ofpolymethyl (meth)acrylate, the polymerization degree is preferably about900 to 1800, and if the polymerization degree is larger than the aboverange, a low molecular material having an action to provide theplasticity has to be added to lower the thermal deformation temperature.

On the other hand, the polyester resins described above includepolyester resins represented by polyethylene terephthalate, polybutyleneterephthalate, ethylene•terephthalate•isophthalate copolymers and thelike. The polyester resin is a copolymer obtained by ester-bonding bothof an acid component such as aromatic dicarboxylic acid includingterephthalic acid, isophthalic acid, naphthalenedicarboxylic acid andthe like and an alcohol component such as aliphatic diol includingethylene glycol, diethylene glycol, butanediol, hexanediol and the like.

In the surface resin layer 13 of the present invention, a UV absorberand/or a light stabilizer can be added for the purpose of providing thedecorated sheet 10 with a weatherability (light fastness). In this case,an addition amount thereof is usually about 0.5 to 10% by weight in bothcases of the UV absorber and the light stabilizer, and in general, theUV absorber and the light stabilizer are preferably used in combination.Capable of being used as the UV absorber are organic compounds such asbenzotriazole, benzophenone, salicylic esters, triazine and the like andinorganic compounds such as zinc oxide, cerium oxide, titanium oxide andthe like each having a fine particle form of 0.2 μm or less. Hinderedamine base radical scavengers such asbis-(2,2,6,6-tetramethyl-4-piperidinyl) sebacate and the like andpiperidine base radical scavengers can be used as the stabilizer.

Further, in addition to the UV absorber and the light stabilizerdescribed above, powders of calcium carbonate, barium sulfate, clay,talc and the like may be added as a filler. An addition amount thereofis suitably determined according to the uses. Also, powders of aluminumhydroxide, magnesium hydroxide and the like are added as a flameretardant in a certain case to a colored thermoplastic resin layer. Anaddition amount thereof falls preferably in a range of 10 to 150 partsby weight based on 100 parts by weight of the thermoplastic resin.

A thickness of the above surface resin layer 13 has to fall in a rangeof 50 to 150 μm. If the thickness is less than 50 μm, it is difficult todisplay the effects of the above layer, and if it is larger than 150 μm,heat transferred from the injected resin in insert molding is filled inthe decorated sheet in the metal die to cause ink flow in a certaincase. From the viewpoints described above, a thickness of the abovesurface resin layer 13 is more preferably 75 to 125 μm.

(4) Other Layers and Various Treatments

As described above, the decorated sheet 10 of the present invention iscomposed, as described above, of at least the base sheet 11, the printlayer 12 and the surface resin layer 13. However, layers constitutingthe decorated sheet 10 are not restricted to the above layers, and otherlayers can suitably be laminated as well according to the uses of thedecorated sheet and the performances required.

Further, a readily adhesive primer layer (not illustrated) may be formedon a back surface side (a side reverse to a face on which the printlayer is formed) of the base sheet 11 for the purpose of enhancing anadhesive property of the decorated sheet 10 with an adherend.

Curable resins and thermoplastic resins such as various urethane resins,epoxy resins, thermoplastic polyester resins, polyamide resins and thelike can be used for the readily adhesive primer layer. Among them,two-component curable urethane resins are preferred since a goodadhesive property can be achieved to a broad range of adherendmaterials.

A back surface side of the base sheet 11 may be subjected to readilyadhesive treatment in place of forming the readily adhesive primer layerdescribed above or in addition to the formation of the readily adhesiveprimer layer. The readily adhesive treatment includes, for example,corona discharge treatment, ozone treatment and the like.

Further, in the decorated sheet 10 of the present invention, irregularpatterns may be formed as decorating treatment on a part or the wholepart of various layers constituting the decorated sheet 10. A designproperty of the whole part of the decorated sheet 10 can be furtherenhanced by forming the above irregular patterns.

The above irregular patterns can be formed by hair line processing, sandblast processing, emboss processing and the like. For example, in theemboss processing, the irregular patterns are formed by pressing anemboss plate onto the surface of a resin sheet which is heated andsoftened by means of a single layer or rotary type emboss machine of ahot press system. In this case, the resin sheet is the surface resinlayer or the base sheet. The irregular patterns may be formed at thesame time as forming the base sheet and the surface resin layer. Forexample, the irregular patterns are formed at the same time as forming alayer by T die melt extrusion method using as a cooling roller, anembossing and cooling roller having irregular patterns on a coolingface. Further, the irregular patterns can be formed as well by aso-called doubling emboss method in which at the same time as laminatingthe base sheet and the surface resin layer, the irregular patterns areformed on a surface side of the surface resin layer by emboss processingby hot pressing. The irregular patterns include woodgrain plate conduitgrooves, slate palette surface irregularities (granite cleavage planeand the like), cloth surface texture, pearskin finish, sand grains, hairlines, line grooves and the like. The irregular patterns are providedusually on a surface side of the surface resin layer, and they areprovided as well on a back side of the surface resin layer, a surfaceside of the base sheet and a back side of the base sheet in a certaincase.

Further, a colored part can be formed by filling an inside of a concavepart in the irregular patterns with a color ink by a publicly knownwiping method (refer to Japanese Patent Publication No. 14312/1983 andthe like). The same materials as used for the print layer 12 describedabove can be used for the color ink. An ink comprising a two-componentcurable urethane resin as a binder is preferred in terms of the abrasionresistance. The wiping method may be carried out by any of wipingmethods such as a doctor blade method, a roll coating method and thelike which have so far been used. That is, the color ink is coated onthe whole surface of the irregular patterns, and then the ink present onthe convex part is scraped away or wiped off with a doctor blade, asponge roll, a cloth or the like so that the color ink remains in theconcave part.

(5) Adherend for the Decorated Sheet

Adherends (that is, the use of the decorated sheet of the presentinvention) for which the decorated sheet of the present invention isused shall not specifically be restricted, and it can be used forvarious articles formed by the insert molding method. Resin materialsused for the insert molding method include resin materials used in theforms of plates, sterically formed articles, sheets and the like ofacryl resins, polyester resins, polystyrene resins, polyolefin resinssuch as polypropylene and the like, ABS (acrylonitrile-butadiene-styrenecopolymer) resins, phenol resins, vinyl chloride resins, cellulose baseresins, rubber and the like, materials obtained by combining two or morekinds of the above materials, for example, composite (raw) materialssuch as wood powder plastics, paper powder plastics, FRP(fiber-reinforced plastics) and the like which are used in the forms ofplates, sterically formed articles and the like.

(6) Adhering (Laminating) Method onto the Adherend

The decorated sheet of the present invention has been developed for thepurpose that it is used principally for an insert molding method, andtherefore a method of adhering (laminating) the decorated sheet onto theadherend is preferably a method in which the decorated sheet is adheredintegrally on the surface of an insert molded article in insert molding.To be specific, it includes an insert molding method in which thedecorated sheet is disposed, as described in Japanese Patent PublicationNo. 19132/1975 and Japanese Patent Publication No. 27488/1968), betweenboth male and female metal dies for injection molding and in which amolten resin is injected and filled into the dies to mold an adherendwhich is a resin molded article and adhere and laminate the decoratedsheet on the surface thereof at the same time.

EXAMPLES Example 1

An ABS resin having an acryl content of 28% by weight, a butadienecontent of 30% by weight and a styrene content of 42% by weight eachbased on the whole amount and having a thickness of 400 μm was used as abase sheet, and an adhesive comprising a polyester•urethane resin as aprincipal component was coated thereon in a thickness of 8 μm. On theother hand, a print layer having a thickness of 5 μm was formed on aback face side of an acryl resin having a thickness of 75 μm as asurface resin layer by using a print ink comprising a polyester•urethaneresin as a binder component, and then the surface resin layer on whichthe above print layer was formed was laminated on the adhesive describedabove, whereby a decorated sheet of Example 1 according to the presentinvention was prepared.

Example 2

A decorated sheet of Example 2 according to the present invention wasprepared on the same conditions as in Example 1 described above, exceptthat the composition of the ABS resin as the base sheet was changed toan acryl content of 34% by weight, a butadiene content of 24% by weightand a styrene content of 42% by weight each based on the whole amount.

Example 3

A decorated sheet of Example 3 according to the present invention wasprepared on the same conditions as in Example 1, except that thecomposition of the ABS resin as the base sheet was changed to an acrylcontent of 45% by weight, a butadiene content of 15% by weight and astyrene content of 40% by weight each based on the whole amount.

Example 4

The decorated sheet of Example 4 according to the present invention wasprepared on the same conditions as in Example 1, except that thecomposition of the ABS resin as the base sheet was changed to an acrylcontent of 42% by weight, a butadiene content of 12% by weight and astyrene content of 46% by weight each based on the whole amount.

Example 5

A decorated sheet of Example 5 according to the present invention wasprepared in the same manner as in Example 4, except that an acryl resinhaving a thickness of 50 μm was used in place of the acryl resin havinga thickness of 75 μm used as the surface resin layer in Example 4.

Example 6

A decorated sheet of Example 6 according to the present invention wasprepared in the same manner as in Example 1, except that an acryl resinhaving a thickness of 125 μm was used in place of the acryl resin havinga thickness of 75 μm used as the surface resin layer in Example 1.

Example 7

A decorated sheet of Example 7 according to the present invention wasprepared on the same conditions as in Example 1, except that thecomposition of the ABS resin as the base sheet was changed to an acrylcontent of 28% by weight, a butadiene content of 27% by weight and astyrene content of 45% by weight each based on the whole amount.

Example 8

A decorated sheet of Example 8 according to the present invention wasprepared on the same conditions as in Example 1, except that thecomposition of the ABS resin as the base sheet was changed to an acrylcontent of 28% by weight, a butadiene content of 33% by weight and astyrene content of 39% by weight each based on the whole amount.

Example 9

A decorated sheet of Example 9 according to the present invention wasprepared in the same manner as in Example 7, except that an acryl resinhaving a thickness of 125 μm was used in place of the acryl resin havinga thickness of 75 μm used as the surface resin layer in Example 7.

Comparative Example 1

A decorated sheet of Comparative Example 1 was prepared on the sameconditions as in Example 1 described above, except that the compositionof the ABS resin as the base sheet was changed to an acryl content of15% by weight, a butadiene content of 40% by weight and a styrenecontent of 45% by weight each based on the whole amount.

Comparative Example 2

A decorated sheet of Comparative Example 2 was prepared on the sameconditions as in Example 1, except that the composition of the ABS resinas the base sheet was changed to an acryl content of 48% by weight, abutadiene content of 4% by weight and a styrene content of 48% by weighteach based on the whole amount.

Comparison Tests:

1. Bend Elastic Modulus

In Examples 1 to 9 and Comparative Examples 1 to 2 described above, thebend elastic modulus of the ABS resins each used as the base sheet weremeasured by a test method prescribed in ISO 178. The results thereof areshown in the following Table 1.

2. Vicat Softening Temperature

In Examples 1 to 9 and Comparative Examples 1 to 2, the Vicat softeningtemperatures of the ABS resins each used as the base sheet were measuredby a test method prescribed in JIS K 7206. The results thereof are shownin the following Table 1.

3. Laminate Aptitude

A laminate aptitude test was carried out in order to judge the adhesiveproperties of the respective layers constituting the decorated sheetsprepared in Examples 1 to 9 and Comparative Examples 1 to 2. This testwas evaluated by dry laminate. The conditions of the dry laminate wereset to a laminate pressure of 4.5 MPa, a tension of 40 kgf, apenetrate-into-ABS angle of 50 degrees and a penetrate-into-ABStemperature of 80° C. The results thereof are shown in the followingTable 1.

4. Odor

In Examples 1 to 9 and Comparative Examples 1 to 2, an odor test of theABS resins used for the respective base sheets was carried out in orderto judge the rubber odor thereof. The above test was carried out byputting each ABS resin (30 mm×10 mm) into a bottle having a height of100 mm, a diameter of 50 mm and a mouth diameter of 30 mm, leaving thebottle standing at 60° C. for 2 hours after covering it with a cap andthen sniffing it in order by six persons. The cap of the bottle wasopened, and the first person sniffed it at a distance of 5 cm from themouth of the bottle. The cap was closed within 5 seconds, and the bottlewas heated in an oven for 15 minutes. Then, the second person sniffedthe bottle in the same manner, and this was repeated up to the sixthperson.

The evaluation was carried out according to the following six levels andjudged by an average score of total points given by four personsexcluding each one person who gave the highest point or the lowestpoint. The results thereof are shown in the following Table 1. In theactual use, the level of lower than Evaluation 3 is expected to pass thetest.

Evaluation 1: no odorEvaluation 2: odor is felt but is not unpleasantEvaluation 3: unpleasant odorEvaluation 4: very unpleasant odorEvaluation 5: venomous odorEvaluation 6: intolerable odor

5. Insert Moldability

The decorated sheets prepared in Examples 1 to 9 and ComparativeExamples 1 to 2 were used to actually carry out insert molding, and itwas comprehensively evaluated. The results thereof are shown in thefollowing Table 1.

6. Surface Hardness

The decorated sheets prepared in Examples 1 to 9 and ComparativeExamples 1 to 2 were measured for a surface hardness by a pencilhardness method prescribed in JIS. The results thereof are shown in thefollowing Table 1.

TABLE 1 Acryl Butadiene Styrene Bend Vicat content content contentelastic softening (% by (% by (% by modulus temperature Laminate InsertSurface weight) weight) weight) (MPa) (° C.) aptitude Odor moldabilityhardness Example 1 28 30 42 1230 92 Good 2.5 Good F Example 2 34 24 421300 95 Good 2.3 Good F Example 3 45 15 40 1600 98 Good 1.5 Good HExample 4 42 12 46 1800 100 Good 1.5 Good H Example 5 42 12 46 1800 100Good 1.5 Good B Example 6 28 30 42 1230 92 Good 2.5 Good H Example 7 2827 45 1260 94 Good 2.5 Good F Example 8 28 33 39 1100 88 Good 3.0 Good FExample 9 28 27 45 1260 94 Good 2.5 Good H Comparative 15 40 45 900 82Good 4.1 Good 2B Example 1 Comparative 48 4 48 2300 103 X*¹ 1.5 Good HExample 2 *¹air filling and slack were caused

As apparent from the results shown in above Table 1, it has been foundthat the decorated sheets of the present invention are excellent in arubber odor, an insert moldability and the like as compared with thedecorated sheets of the comparative examples.

INDUSTRIAL APPLICABILITY

According to the decorated sheet for insert molding of the presentinvention, the decorated sheet can be provided with variouscharacteristics such as a rigidity, a hardness, a processability, animpact resistance, a bend fatigue property and the like with which anABS resin is endowed. Also, the decorated sheet for insert molding ofthe present invention can be improved in a moldability withoutgenerating a characteristic rubber odor originating in a butadienecomponent in bringing the decorated sheet into contact with a resinmolten at 200° C. or higher in insert molding. Further, the inkconstituting the print layer does not flow due to heat, and thereforethe design property can be maintained. From the viewpoints describedabove, the decorated sheet for insert molding of the present inventioncan be used for various applications, and it can suitably be usedparticularly for decoration of interior panels of cars and the like.

1. A decorated sheet for insert molding in which at least a base sheet,a print layer and a surface resin layer are laminated, wherein the abovebase sheet comprises an ABS resin having a butadiene content of 10 to33% by weight based on the total component, and the surface resin layerhas a thickness of 50 to 150 μm.
 2. The decorated sheet for insertmolding as described in claim 1, wherein the base sheet has a Vicatsoftening temperature of 85 to 100° C. and a bend elastic modulus of1100 to 2000 MPa.
 3. The decorated sheet for insert molding as describedin claim 1, wherein at least a thermoplastic resin is contained in theprint layer.
 4. The decorated sheet for insert molding as described inclaim 2, wherein at least a thermoplastic resin is contained in theprint layer.